Stitch-forming mechanism for sewing machines



July 18, 1950 D. G. SMITH ET AL 0 STITCH-FORMING MECHANISM FOR SEWINGMACHINES Filed Nov. 14, 1947 6 Sheets-Sheet l g vvuwnliobb .Darwin G.Smith and A JJwroZoZ alzzwZbz/zer July 18, 1950 v D. G. SM ITH ETALSTITCH-FQRMING MECHANISM FOR SEWING MACHINES Filed Nov. 14, 1947 6 Sheets-sheet 2 hwmbaza @arwin 6'. Smith and Jfarold Cf/Zzul/Qner 3 v@tbozneyy July 18, 1950 D. G. SMITH ET AL STITCH-FORMING MECHANISM FORSEWING MACHINES 6 Sheets-Sheet 5 Filed Nov. 14, 1947 Qnvemco'u Darwin G.Smith and Jlzrold Cikulner awn mew July 18, 1950 D. G. SMITH ETAL2,515,740

H STITCH-FORMING MECHANISM FOR SEWING MACHINES Filed Nov; 14, 1947 6Sheets-Sheet 4 atto'unayy July 18, 1950 D. G. SMITH ET AL 2,515,740

STITCH-FORMING MECHANISM FOR SEWING MACHINES Filed Nov. 14, 1947 6Sheets-Sheet 5 T mm L July 18, 1950 D. 6. SMITH ET AL 2,515,740

-- STITCH-FORMING MECHANISM FOR SEWING MACHINES Filed Nov. 14, 1947 v eSheets-Sheet a Darwin 6'. Smith and WWW: 5 Harold C. Faulkner PatentedJuly 18, 1950 2,515,740 PATENT OFFICE,

STITCH-FORMING MECHANISM FOR SEWING MACHINES Darwin; G, Smith and HaroldC. Faulkner, Bridgeport, 0o,n n., assignors to The Singer Manufacturing;Company, Elizabeth, N. J a corporation of New JerseyApplicationlNovember 14, 1947, Serial No. 786,017

ltQ a ms- 1 This invention relates primarily to -an; improve:

ment in o rs amine st h iermina m c anism.

and more particularly of that class embodied, in

eyelet stitching machines in which the stitchqv It is th o ject: of th pes nt: nv on to provide an. eyele s w-ins ma h ne-havin an-im provedstitch-forming mechanism; capable, of pro-.

ducing eyeletswithinthe range of sizesindicated bove and requiring aminimum of simple ma chine adjustments in pr duci this ran e; of;eyelets.

Another object of the present. invention; is to.

provide a simplified stitcheforming; mechanism composed of sturdiercomponents with good mechanieal movements, the, present. constructionbeing in the nature of an improvement over the construction disclosed inthe U. S. Patentof. B. Allen, No. 1,162,207, dated Nov. 30, 19.15.-

With the above and other objects in View, as

will. hereinafter appear, the invention comprises,

the devices, combinations and arrangements of arts her inafter s t fo thand illustrated in t e accompanying drawings of a preferred embodir mentof the invention, from. which the several, featuresof the invention andtheadvantages a1;- tai ed. he y W ll e readily unde st od. ytseskilled-in the; art.

n. the ac panying draw n s;

F 1 is a r ht side. leva eha v ew. partly n s of. an yelet sewing. machn em od ing the invention.

F 2 s a fr nt levati hal. vi w. partly section, of the sewingmachinehead with the fa e plate removed to. show the needle-baractuating connections.

Fi 3 i a front, end levat on ew. partly in section, of the.sewingmaohine, showing the driving mechanism for the lowerstitcheforming elements.

Fig. 4 is. a top plan view of'the machine-bed withthe usualwork-clamping means removed to show better the turret and the componentsof;

Fig. 7 represents a horizontal sectional view taken substantially alongthe line 'l-.|, Fig. 5,.

Fig. 8 is a vertical section taken through the, turret, showing, in fulllines, the curved needle at the lower end of its; strokeand, in dottedlines, at the upper end of its stroke.

Fig. 9 is a side elevation, partly in section, of;

the curved needle clamp.

Fig. 10. represents a vertical sectional viewtaken substantially alongthe line Ill-10, Fig. 4

Fig. 1 1 is an enlarged vertical sectional view taken substantiallyalong the line !l-.-.l I, Fig, 4,

showing the means by which the stroke, of the curved needle is adjusted.

Fig. 12 is a top plan view of the. slotted element. in Fig. 11, showingthe graduations. whi aci h tate the proper adjustment of the. stroke ofthe, curved needle.

Fig. 13 is an enlarged right side elevational view of the straightneedle. hold r. showing.

do ted lines, th ex reme pesit onsei lat ral a liustme t oi h eedle.

Fig. l4. is a sectional view taken substantially on the li e Fig- 1.3;

Fi 15 i a erticalseet hal V ew at th t tchr n po n showin he urved,needle advancin t pres nt ts t r ad. or entranc by. the. escend:

ins rai h e dle.

16 is a. iew simila to Fi wi ur d needle. inst beginnin ts return.motion after having presented its thread to the straight.

needle.

Fia s. an nlar e v op plan view. w th the. ne d e n se t on... ce ain ohe par s. Desi;- tioned as shown in Fig. 16.

Fig. 18 is a view similar. to Fig. 15, but. with the curved needlethread-loop entered by the straight needle which has penetrated thefabric and reached the bottom of its stroke.

Fig. 19 is. a View of the curved needle actuating connections, showing,in full lines, the position of the, parts. when the curved needle is at"the bottom of its dip at the upper end of its stroke and, in dottedlines, the position of the parts shortly after the curved needle has,begun its return stroke.

Fi 2 is a sectional view. showin th part in the next position ofstitch-formationwith he looper seizing the straight needle thread-loopand the curved needle descending through the. out.

eyein the fabric.

Fig. 2i is a top plan View, with the needle section, of certain of theparts as positioned as.

shown in Fig. 20, illustrating the looper-seizing the straight needlethreadeloop.

Fig. 23 is-a top plan view, with the needledn.

in the next position with the looper at the end of its loop-seizingstroke and with the straight needle thread-loop expanded and held overthe point of the curved needle for entrance thereby.

Fig. 25 is a top plan view of the looper and its carrier in the positionconforming to that shown in Fig. 24.

Fig. 26 is an elevational view of the curved needle actuating mechanism,showing the position of the parts when the curved needle is at the lowerend of its stroke.

Fig. 27 is an enlarged perspective view of the needle-bar guide-piece,showing its widthwise adjustable spline which tracks a groove in theneedle-bar. Figs. 28 and 29 are illustrations of the top and bottomsides, respectively, of the completed eyelet as produced on a machineequipped with the present invention.

Fig. 30 is a development of the stitching as producedb'y a machinefittedwith the present looper mechanism.

Fig. 31 is a view similar to Fig. 30, but illustrating the stitching asproduced by prior machines.

Referring more in detail to the drawings, the present illustratedembodiment of the invention includes a machine frame having arectangular base I from which rises a hollow standard 2 having thetubular overhanging bracket-arm 3 terminating in a head 4. The base I isshown resting on a bed-plate 5. Within the base I is suitably joumaled amain sewing shaft 6, Fig. 1, which, through the one-to-one bevel gears 1drives a vertical-shaft 8 journaled within the standard 2. The shaft 8has a one-to-two speedmutliplying bevel-gear driving connection 9 withan upper or needle-bar-reciprocating shaft In which is journaled withinand lengthwise of the bracket-arm 3. Secured to the front end of theshaft, I0 is a crank II connected by a link I2 to averticallyreciprocatory needle-bar I3 journaled for endwise movement in the head4. Carried at the lower end of the needle-bar I3 is the usualstraight-depth-stitch needle I4 which can be adjusted sidewise orlaterally of the needle-bar to effect a change in the size of theoutside diameter of the eyelet. To provide for this lateral adjustment,the needle I4 is secured in a two-piece needle-clamp comprising a fixedpart and a movable part, the clamp being best shown in Figs. 13 and 14.The shank I5 of the needle I4 is secured in the movable part I6 of theclamp by a setscrew IT. The movable part I6 and the fixed part I8 of theneedle-clamp are fastened together by a clamp-screw I9 extending throughan elongated clearance opening 20 in the fixed part I8. It will beobserved that one face of the movable part I6 is provided with aninclined tongue M which fits into a groove 22 formed in the adjacentface of the fixed part I8. By loosening the screw I9 the movable partcan be shifted relative to the fixed part along the inclined axis of thegroove 22. Thus, when the needle I4 is adjusted in a direction away fromthe axis of the needlebar I3 it is raised and when it is adjusted towardthe axis of the needle-bar I3 it is lowered. The resultant verticaladjustment of needle properly positions the needle-eye I4 with respectto the beak of the complemental looper, later to be described, thusinsuring the formation of a sufiicient loop of needle-thread for seizureby the 4 looper for large eyelets as well as for small eyelets. Tofacilitate accurate shifting of the needle I4 to its proper lateralposition, the fixed part I8 of the needle-clamp is provided withgraduations 23, Fig. 13, representing the diameter of the finishedeyelet and complemental to these graduations is a pointer 24 pivotallymounted on a pin "24' and apertured at 25 to receive the clampscrew I9.Adjustment of the movable member I6 of the needle-clamp will cause thepointer 24 to pivot on the pin 24' and play over the graduations 23,thus indicating the lateral setting of the needle l4.

In order to disperse .the stitches uniformly about the eyelet, theneedle-bar I3 is caused to make one complete revolution during eachstitching cycle. To that end, the needle-bar I3 has its upper bearing ina bushing 24", Fig. 2, carried in the upper wall of the head 4, and itslower bearing in a rotary bushing 25', Fig. 3, journaled in the lowerwall of the head 4. The rotary bushing 25' is provided beneath the head4' with a toothed pinion 26 and has threaded thereon above the wall ofthe head a collar 2'! by which the bushing is maintained in position.Beneath the pinion 26, the bushing 25 is formed with a collar 28, Fig.3, to which is secured, by a screw 29, a guide-piece 30 having a key orspline 3| entering a groove 32 in the side of the needlebar I3. Thespline SI and groove 32 cooperate to confine the needle-bar I 3 fromturning relative to the bushing 25 while permitting the needlebar toreciprocate freely. It will be observed in Fig. 27 that the spline 3I isvertically slotted, dividing the same into two halves which can berelatively widthwise adjusted by the screws 3 I so that the spline maybe made to accurately fit the groove 32 in the needle-bar I3. As shownin Fig. 2, the link I2 at its lower end is connected to a sleeve 33confined between a shoulder 34 on the needle-bar I3 and a collar 35clamped on the needle-ban,

Cooperating with the straight depth-stitch needle I4 is theunderstitching mechanism com prising a loop-presenting lower overedgeimplement or curved needle 36 and a lower looper 37. both mounted on arotary turret 38 and actuated in a manner later to be described. Theturret 38 is provided with a pinion 39, Fig. 1, similar to the pinion 26on the needle-bar bushing 25, the pinions 26 and 39 meshing with toothedsectors 40 which are preferably mounted on separate but alined fulcra4|. These sectors 43 have lateral arms 42 which are connected byadjustable links 43 to upper and lower cranks 44 on a vertical shaft 45,the lower crank carrying a cam-follower roll 46 entering a suitable camgroove in the un der face of the usual feed-cam 41'. The mechanism justdescribed slowly turns the stitch-forming instrum-entalities about avertical axis in a counterclockwise direction, when viewing the machinein top plan, during the sewing operation.

sewing shaft 6, the period of operation of which,

is controlled by the regular stop-motion 48, all as disclosed in theabove mentioned Allen Patent No. 1,346,102.

Journaled in the machine-frame are two transanrtrmo verseiorcross'shafts49;: and 50, Fig. 1. Shaft 49- performs a single rotation prior tosewing and carries cams" (not shown) which act to close the work-clamp Iupon the work and to tilt the stop-motion lever48 into; runningposition. Also operatedby shaft 6% is the. eyelet cutting, device 52,fully described. in another patent application filed in the name of H.C. Faulkner. Shaft 50 performs a single rotation after sewing iscompleted. It is. formed with a crank 53 which acts through the link 5'4to swing the arm 55 and pawl 56.. and impart a rapid motion to thefeed-wheel 41: in. one. sweep of the arm 55, after the sewing is.completed, to restore the feed-wheel to its initial position. This rapidmotion of the feedwheel 41 repositions the upper and under stitchingdevices to their initial sewin positions. These cross shafts 49 and 59,together with their driving and controlling connections are well known;being constructed substantially in accordance withthe disclosure in theAllen Patent No. 1,346,102.

As previously mentioned, the lower curved nee dlev 36 and the looper 3'!are mounted on the turret 38 which is provided with a depending hollowspindle 51 journaled for turning movement in the turret-bracket fastenedto the machine basel. Endwise slidable in the bore of the spindle 5.1 isthe usual actuating rod 59 driven in a manner fully disclosed in theAllen Patent No. 1,162,207. Generally speaking, the actuatin rod 59,Figs. 1, 3, l9 and 26 at its lower end is embraced: by one end of alaterally extending head 60. confined at its other end between collars6i threaded on a driving rod 62 vertically reciprocable in theturret-bracket 58. The driving rod 62 is reciprocated in its bearings bymeans of the interconnected toggle-links I53 and 64 which are. connectedby alink 65 to a crank 66 carried on the outer end of a shortlooper-actuating shaft 61. The inner end of'the looper-actuating shaft6'! has mounted on it a gear 68 meshing with a gear 69 twice its sizeand fastened on the-main sewing shaft 6. Through the connections justdescribed, the crank 66 has imparted to it uniform rotary motion inunison with that of the needle-bar crank II. The crank 66 imparts to thedriving-rod 62, through the toggle links 63, 64, an interruptedreciprocatory motion which, throughthe mechanism carried by the turret38, operates the curved needle 36 and. looper 37.

Referring now to'Figs. 4, 5, 6 and 7, it will be seen that theloop-presenting implement or curved needle 3G and the looper 31 areactuated by connections with a laterally offset head III on the upperend of theactuating rod 59. To steady the oifsethead it it is bifurcatedat its free end and straddles-a guide-rod "II upstanding from the turret38. The curved needle 36 is operated from the offset head W by means ofa ball-stud I2, Fig. 8, connected by a link I3 to a ball-stud I4 carriedby a needle-carrier rock-arm I5. The rock-arm E5 is attached to aneedle-carrier IS,

formed in the usualoifset needle-throat member 83 adjustably' supportedon the turret 38; the

straight needle reciprocating through the opposite? end of the aperture82 after penetrating the fabric to produce the depth-stitch.

When adjusting the size of the sewing circle or eyelet, as by shiftingthe needle I4 sidewise of I the needle-bar I 3, the stroke of the curvedneedle Figs. 8 and 11, supported for vibration on a pivotcated throughone end of a suitableaperturetz:

36-: need not be changed unless there is an ex cessiveamount of' lowerthread for the'size of the eyelet being. produced. To provide forregulatingrthe stroke of the curved needle 36, the needle-carrierrocki-arm 75, Fig. 11 is slotted, as at 8d,. to-receive a clamping screw85 passing through a. clamp-plate 86' and threaded into theneedlecarrier it. To facilitate adjusting the rock-arm- 'isdrelative totheneedle-carrier I6, the rock-arm 7:55. is provided with graduations81, Fig. 12, andthe clamp-plate: 86 is provided with a complementalindicator toe 88. It will be understood that whenincreasing' the size ofthe eyelet. the

stroke of the curved needle 36 need be increased only to createsufiieient throwof the curved needle so that its eye will travel beyondthe path ofL'the straight needle, thereby to present a loop of lowerthread in position for the straight needle to enterthe loop. Referringto Fig. 8, it will be seen that adjustment of the rock-arm I5 relativeto:v the. needle-carrier It, when the curved needle 36 is at the lowerend of its. stroke, will result in ashifting of the ball-stud 'l'lsubstantially along a linear +11. which ispreferably normal to thelinex-:1:connecting the two ball-studs "I2 and I5. Thiseffects a turningofithe link l3 about the axis of the-ball-stud 12 without causing anynoticeable shifting of the needle-carrier it about its pivot-stud W.Thus, the stroke of the curved needle 36 is changed'ati its upper endonly, while maintainin the necessary fixed relative positionofthe-curv'ed needle at the lower end of the stroke with respect to thatof the looper at the end of its needle-thread-loop presenting stroke.

The improved looper mechanism, as previously mentioned, derives itsmovements from the offset head lIl on the reciprocatory actuating-rod5'9. To that end, the offset head ill is provided;

with a stud 89, Figs. 6 and 7,,upcn which is pivotally mounted aslide-block 90 fitted into a slot 9| formed in an oscillatory bell-cranklever 52 fulcrumed on the stud E3. on the turret 38. Pivoted on theoscillating lever 52, as at 94, is a slideblock 9!: entering a verticalslot 96 formed in the back plate Qlof a looper-actuating slide-mem ber98; adapted'to track a guide-way 99 formed in a: vertical plate-memberIIlIl preferably fastened by screws IEEI to the turret 38. Secured tothe slide-member 98, as by screws I02, on the outside of the verticalplate-member IUU, Fig. 5, is right: angle carrier or looper-supportingbracket I03, the screws 62. preferably serving to maintain thesupporting bracket I03, the slidemember 96 and the back plate 91 inassembled face-to-face relation. Pivoted, as at I04, on the free end ofthe horizontal limb of the loopersupportingbracket its is one of a pairof interconnected toggle-links I05, I06; the two links beingsubstantially longitudinally alined and hinged-together by ascrew Ill?which serves as aknuckle-pin for the two toggle-links. The link I616 isfitted with two depending rollers I 03 which are adapted to track acam-groove I09 milled in the upper face of a cam-plate Ill] secured byscrews III to the turret 38. The toggle-link I05- has cut into its upperface a transverse slot IIZ,

Figs. 23 and. 25, into which is inserted the shank H3 of the looper 31,the shank II3 having an elongated opening IM for a clamp-screw II5 bywhich the looper 31 is mounted for limited adjustment to accommodateneedles of various sizes. The looper 31 is formed with a loop-seizingbeak II6 terminating in a throat I I1 disposed to sufficiently expandthe needle-thread-loop, as will be described later. Spaced below thebeak I I6 is a needle-guard IIB having a curved needle-contacting edge II9 which assists in properly locating the straight needle I4 during theactual seizing of the thread-loop by the beak of the looper. To minimizetilting of the looper 31 out of its horizontal plane of movement, thetoggle-link I06 has fastened to it an inverted U-shaped guide I20 ofwhich the limbs straddle the link I96 with the lower ends of the limbspositioned to slide on the upper face of the cam-plate III], as shown inFig. 3. It will be understood from the foregoing that the reciprocatingactuating-rod 59 through the slide-block 90 carried by the ofiset head land the slot 9|, imparts an oscillatory movement to the bell-crank lever92 about the stud 93, and that the oscillations of the bell-crank lever,through the slide-block 95 and slot 96, transmit to the looper-actuatingslide-member 98 a variable reciprocating motion. The motions of theslidemember 98 are transmitted to the looper-carrying toggle-link I05,and the cam-groove I09 effects a making and breaking of the toggle-linksI and I06 about the knuckle-pin I01, thereby to combine with theloop-seizing and loop-shedding movements of the looper lateral movementsfirst to avoid collision with the curved needle 36 and second to carrythe seized straight-needle thread-loop over the point of the curvedneedle so that the latter on its upstroke may enter the expandedstraight-needle thread-loop.

To aid in describing a cycle of operations of the stitch-formingmechanism, attention is directed to Figs. 15 through 26, inclusive. Letit be understood that during the stitching the work W is securely heldon the bed-plate of the machine by the usual work-clamp 5| and that theupper straight needle I i, carrying the upper thread U penetrates thework W to form the depth-stitches which define the outside periphery orsize of the eyelet; while the lower curved needle 36 carrying the lowerthread L reciprocates through the usual center eye I2I cut or punchedinto the work preferably before the stitching starts, thus laying itsthread L about the edge of the eye I25. With this in mind, assume nowthat the machine has produced several stitches and that the parts are inthe position shown in Fig. 15, with the straight needle Id at the top ofits stroke and the curved needle 36 rising through the eye I2I in thework W after having entered the upper thread-loop U presented by thelooper 31. The curved needle 36, during its rise through the eye in thework W, is moving very rapidly since the actuating crank 66 is movingthe toggle-links 63, 64 upwardly toward their straightened position.Meanwhile, the looper 31 is retracting and the straight needle I4 has asubstantial dwell at the upper end of its stroke, since the needle-baractuating crank II is passing through its highest point, as shown inFig. 2. Proceeding with the cycle, the curved needle 36 continues in itsrapid rise to the upper end of its stroke and the looper moves to itsextreme retracted position just as the toggle-links 63, 64 reach theirstraightened position, but as the toggle-links move slightly paststraightened position, as represented in full lines in Fig. 19,

the actuating rod 59 receives a slight dip in its upper position whichdip is communicated to the lower curved needle 36 to cause it to castout a loop of its thread L above the work W for entrance by thedescending straight needle I4, as shown in Figs. 16 and 17; the looper3'! being given a corresponding idle movement adjacent its extremeretracted position. The straight needle I i, after entering the curvedneedle threadloop L penetrates the work W, Fig. 18, and continues in itsdescent to the bottom of its stroke, during which time the curved needle36 rises again to the upper end of its stroke and then begin its descentback through the eye in the work. During the return stroke of the curvedneedle 36, the straight needle It begins to ascend, Figs. 20 and 21, andin so doing casts out a threadloop which is seized by the beak H6 of theadvancing looper 3?. While the looper 37 is advancing from its fullyretracted position to and slightly beyond loop-seizing position, the tworollers I08 carried by the link I66 are traveling in the straightportion of the cam-groove I09, and thus the looper 3'! is caused to movein a straight line. After seizing the thread-loop presented by thestraight needle It, the looper continues in its movement to expand theseized thread-loop, as shown in Figs. 22 and 23. As the looper 31approaches the curved needle 36, it is moved sidewise or laterallyslightly to avoid striking the curved needle, the sidewise movement ofthe looper being effected by a buckling of the togglelinks I95, I96(Fig. 23) resulting from the rollers I88 traversing the first curve inthe cam-groove I69. Continued movement of the looper to its extremeadvanced position, illustrated in Figs. 24 and 25, will cause a reversebuckling of the toggle-links I65, I96, which carries the beak II6 of thelooper 31 in a curved path around the needle 36 to the position shown inFig. 25. Thus, the

looper 31 carries the straight-needle thread-loop U directly over andabove the point of the curved needle 36. During the travel of the looper31 around the curved needle 36, the latter descends into its lowermostposition where it undergoes substantially a dwell resulting from thecrank 66, Fig. 26, moving through its lower dead center position. Thisso-called dwell of the curved needle 36 gives the looper ample time tomove the straight needle thread-loop U across the point of the curvedneedle 36 before the same begins to rise. The throat II'I on the looper31 is formed and disposed relative to the looper-beak II6 so as tospread the two limbs of the straight needle thread-loop U wherebyentrance by the curvedneedle point into the thread-loop is assured. Theexpanding of the straight-needle thread-loop U the rise of the straightneedle I4 to its highest position and the descent of the curved needle36 to its lowest position all contribute to the setting of thepreviously formed stitch.

It will be understood that to form the stitches properly the curvedneedle 36 must descend to a position in which its point is below theexpanded straight-needle thread-loop U so that said curved needle on itsascent may enter the threadloop U This relation between the curvedneedle 36 and the looper 31 is shown in Fig. 24. It is also necessaryfor proper concatenation of the sewing threads for the curved needle 36to rise sufliciently far at the upper end of its stroke as to presentits thread L for seizure by the descending straight needle I4. Thisrelation between the straight needle and the curved needle is shown inFig. 16. When changing the size of the-eyelet, asbyshifting the needlel4 sidewise relative to theaxis of the needle ba'r l3, the only elementof the stitch-forming mechanism which is moved is the straight needle M.It follows then that, if the change in the size of the eyelet isconsiderable, the stroke of the curved needle 36 must be correspondinglychanged, and at the upper end of the stroke only, in order to maintainthe proper relation with the straight needle 14,- as shown in Fig. 16.When reducing the size of 'the eyelet, it is necessary to shorten thestroke "of the curved needle 36 only when the length of thread L pulledfrom the supply is in excess of that 'ca-pableof being taken up orhandled'by the curved needle and the usual associated thread controls.

The eyelet produced by a machine fitted with the present improvedstitch-forming"mechanism :isillustrated in Figs. 28 and '29; Fig. 28showing the stitch-formation as it'appears on 'the upper face 'of thework W, this being thesam'e asin the regular eyelet, and Fig. 29 showingthe s'titchtdr-mation as it appears on the lower face of the workW,'this being difierentthan the lower face oi'the regular eyelet. Adetailed description of the eyelet will not be-given herein,'inasmuch asthe-'eyelet per se forms the subject of patent application Serial No.786,013, filed November 14,1947, :in th'e name of Darwin G. Smith.Suffice to say that the under face of'the eyelet has, in effect, an

embossed or padded appearance closely approximating that of a-handstitched eyelet, the embossed appear'ance resulting from the loop ofupper thread U passingover, then transversely uhd'er and back over theunder thread L as shown in Fig. 29. This particular concatenation o'f'thetwo threads U and L is obtained by virtiie of the fact that thelooper 31 passes the "curved needle 36 on that side which is adjacentthe 'previous stitch in the work, which in the present case is the rearside of the curved needle, i. e. theside away from the direction offeed. As 'a result of this, the lead of the lower thread L from the laststitch to the eye in the curved needle is over the loop of, upper threadU expanded by the looper 31, as shownin Fig. 30. In previous machines ofthe type disclosed in the Allen Patent No. 1,162,207, the looper passedthe curved needle onthe front side thereoflresulting in the lead of thelower thread L -being below the-loop of upper thread 'U expanded by thelooper 31, as shown in Fig. 31.

From the above, it will be understood that the present looper mechanismprovides a sturdy construction with good mechanical movements, themechanism also being capable of convenient assembly and adjustment.Furthermore, the improved mechanism eifects the production of an eyeletmore nearly simulating a hand sewn eyelet, the stitches composing theeyelet having a novel concatenation which permits setting the stitchwith greater ease. In addition the improved mechanism increases therange of the machine, permitting the production of various sizes ofeyelets with a minimum of necessary adjustments.

It is evident that the looper mechanism herein shown and described,while designed particularly for embodiment in that class of eyelet orbuttonhole machines in which the stitch-forming mechanism rotates, isnot limited in its adaptation to particular 'typepf machine, it beingessentially part of an overedge stitching mechanism which may beemployed in a straight stitching machine of the overedge type.

Having thus set forth the nature of the invention, what we claim hereinis:

l. A looper mechanism for a sewing machine having complemental upper andlowerneedles, comprising a bodily movable carrier, means for actuatingsaid carrier, toggle-links anchored to said carrier for actuationthereby, a looper secured to one of said toggle-links and having a pathof movement to seize a, thread-loop from one of said needles and presentit to the other of said needles, and means 'for controlling relativemovement of said toggle-links during actuation of'said carrier.

2. A looper mechanism for a sewing'm'achine having complemental upperand lower needles, comprising a reciprocating carrier, means forimparting movements to said carrier, a, pair of toggle-links anchored tosaid carrier for actuation thereby, a looper fastened to one of saidtoggle-links and adapted to seize a thread-loop from one of said needlesand present it to the other of said needles, a cam-track disposedadjacent said toggle-links, and cam-follower means secured to one ofsaid toggle-links and engaging said cam-track for controlling thetoggle-links during the movement of said carrier.

3. A looper mechanism for a sewing machine having complemental upper andlower needles, comprising a movable carrier, means for imparting motionto said carrier, 2. pair of toggle-links pivoted at one end to saidcarrier, a looper supported by one of said toggle-links and adapted toseize a thread-loop presented by one of said needles and carry saidthread-loop into position to be entered by the other of said needles, acamtrack disposed below said toggle-linksand a plurality of rollersdepending from one of said toggle-links and extending into engagementwith said cam-track for controlling the toggle-links during themovements of said carrier.

4. A looper mechanism for a sewing machine having an upper needleturnable about an axis, a turret turnable about said axis, and a lowerneedle supported by said turret, comprising a reciprocatory carrierslidably supported on said turret, a pair of tandem arrangedtoggle-links pivoted at one end to said carrier, a looper secured to oneof said toggle-links, a cam-track provided on said turret below saidtoggle-links, and a pair of rollers depending from one ofsaidtoggle-links and cooperating with said cam-track for imparting bucklingmovements to said to gle-Jinks during reciprocation of said carrier.

-5.. A looper mechanism for a sewing machine having a turret, includingan actuating rod, a

lever pivoted to said turret, means operatively :connecting said lever-to said actuating rod, a carrier slidably mounted on said turret, meansoperatively connecting said carrier-to said lever, interconnectedtoggle-links supported by said carrier, a looper secured to one of saidtoggle-links, and means for controlling the toggle-links 'during.the-sliding movement of'said carrier.

6. A sewing machine having a'reciprocatory upper needle, loop-takingmeans including a movable looper adapted to seize thread aloops from theupper needle :at one side of the work and a reciprocatory lower'needleadapted to carry a thread-loop through the upper needle threadloopandpresent it for entrance by the upper needle at the opposite side ofthe work, a'movable carrier, means for imparting movements to saidcarrier, means movably supporting said looper on said carrier, and meansfor controlling said looper so that after seizing the upper needlethread-loop said looper travels in a path between the lower needle andthe previous stitch in the work.

7. A sewing machine having a reciprocatory upper needle, loop-takingmeans cooperating with said needle in the formation of overedge stitchesincluding a reciprocatory lower needle adapted to carry a thread-loopthrough the upper needle thread-loop and present it for entrance by theupper needle and an upper needle threadloop seizing looper having aloop-expanding path of movement between the lower needle and theprevious stitch in the work, and means-for actuating said looper.

8. A sewing machine having a work-support,

a reciprocatory upper needle, means for eiiecting a relative shiftbetween said upper needle and the work, loop-taking means including amovable looper adapted to seize thread loops from the upper needle atone side of the work and a reciprocatory lower needle adapted to carry athread-loop through the upper needle threadloop and present it forentrance by the upper needle at the opposite side of the work, a movablecarrier, means for imparting movements to said carrier, means movablysupporting said looper on said carrier, and means constructed andarranged for controlling the movement of said looper so that afterseizing the upper needle thread-loop said looper passes the lower needleon the rear side thereof with respect to the direction of relativelateral shift between said upper needle and the work.

9. A sewing machine having a reciprocatory needle-bar, a needle carriedthereby, means for shifting said needle sidewise relative to the axis ofsaid needle-bar, complemental loop-taking means including a movablelooper and a vibratory loop-presenting implement cooperating with saidlooper and said needle, a carrier for said looppresenting implement, afulcrum about which said carrier pivots, an actuating rod, and meansoperatively connecting said rod to said carrier including a linkconnected at one end to said rod and a rock-arm connected to the otherend of said link, and means connecting said rock-arm to said carrier forregulating the stroke of said looppresenting implement.

10. A sewing machine having a reciprocatory needle-bar, a needle carriedthereby, means for shifting said needle sidewise relativ to the axis ofsaid needle-bar, cooperating loop-taking means including a movablelooper and a vibratory looppresenting implement cooperating with saidlooper and said needle, a carrier for said looppresenting implement, afulcrum about which said carrier pivots, an actuating rod, and meansoperatively connecting said rod to said carrier including a linkconnected at one end to said rod and a rock-arm connected to the otherend of said link, and means connecting said rock-arm to said carrier forregulating the stroke of said loop-presenting implement, said last-namedmeans being constructed and arranged so that an adjustment of therock-arm relative to the carrier will shift the pivotal connectionbetween the link and rockarm in a direction substantially normal to aline drawn between the pivotal connection of the rock-arm with the linkand the pivotal connection of the other end of the link with saidactuating rod.

'11. A sewing machine having a reciprocatory needle-bar, a needlecarried thereby, means for shifting said needle sidewise relative to theaxis of said needle-bar, cooperating loop-taking means including amovable looper and an oscillatory loop-presenting implement cooperatingwith said looper and said needle, a carrier for said loop presentingimplement, a fulcrum about which said carrier pivots, an actuating rod,and means operatively connecting said rod to said carrier including alink connected at one end to said rod, and a rock-arm connected to theother end of said link, said rock-arm having an elongated hole extendingthrough it, and a screw projecting through said elongated hole andthreaded into said carrier for clamping said rock-arm to said carrier.

12. A sewing machine having a reciprocatory needle-bar, a needle, meanssecuring said needle to said needle-bar with capacity to shift saidneedle sidewise relative to said needle-bar, cooperating loop-takingmeans including a movable looper adapted to seize thread-loops from saidneedle at one side of the work and a vibratory loop-presenting implementadapted to carry a thread-loop through the needle thread-loop andpresent it for entrance by the needle at the opposite side of the work,means for actuating said looper and said loop-presenting implement, andmeans for varying the stroke of said loop-presenting implement toaccommodate the different shifted positions of said needle.

13. A sewing machine having a reciprocatory needle-bar, a needle,adjustable means securing said needle to said needle-bar providing forboth sidewise and endwise shifting movements of said needle relative tosaid needle-bar, cooperating loop-taking devices including a movablelooper adapted to seize thread-loops from said needle at one side of thework and a vibratory loop-presenting implement adapted to carry athread-loop through the needle thread-loop and present it for entranceby the needle at the opposite side of the work, means for impartingoperative movements to said looper and said loop-presenting implee ment,and means for changing the stroke of said loop presenting implement toaccommodate difierent shifted positions of said needle.

14. A looper mechanism for a sewing machine having complemental upperand lower needles,

comprising a slidable carrier, means for sliding REFERENCES CITED Thefollowing references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Hill Nov. 8, 1921 Number

